Fitting Sound and Lamps to an 'old' Hornby A3

[zr2498]

I've a couple of A3s which have been waiting for DCC conversion for quite some time.

The idea behind this project was to see just what was possible, and to take in some learning on working loco lamps.

 

So included is; Locoman sound and large EM1 speaker, firebox flicker, stay alive and working front and rear lamps.

 

As there would be lots of kit to install in the loco, the decoder plug was in the wrong place (tender). That would require a stack of wires between loco and tender (not good). On opening up the loco, it was clear that the 8 pin DCC socket had been located on top of the loco chassis on even older models,  so transfer to the loco should be possible.

 

 

This was the kit used:

 

First the tender. The 8 pin plug was disconnected and the weight removed. The tender pickups had to be disconnected and then resoldered.

 

 

As the decoder would be moved to the loco, the existing 4 pin plug between loco and tender was modified. The outer two pins remained as L & R track pick ups, and the two centre pins would be the new speaker connections.

An EM1 speaker was to be installed.

 

 

The lugs for fitting the weight, and the existing speaker surround was clipped off. The lugs were also cut off the EM1 speaker, and the EM1 speaker cable was connected to the 4 pin plug.

 

 

Speaker installed using black tack.

 

 

The coal chute was cut out of the tender body.

 

 

The rear tender lamp (red), would be connected to the loco via a 2 pin JST connector.

 

 

Preparation of the DCC Concepts lamps. Painting was done using the same method as on the Q6. Black primer, and then an off white. Sadly, DCC concepts no longer have these lamps available, but they are looking to introduce them again - hopefully. I could not get LNER lamps, so LMS / BR had to used.

 

 

The lamp was installed together with a 50K ohm resistor in the positive leg. The positive would connect to Blue +ve common, and the negative return to the yellow wire (rear lights).

 

 

Tender body fitted.

 

 

 

The next part will cover the installation in the locomotive.

 

 

[zr2498]

Now for the A3 locomotive modification.

The 8 pin plug (moved from the tender), was prepared for connections. The purple wire should be white, but I couldn't find any white wire! Red is also motor +ve (orange) and Black motor -ve (grey).

 

 

 

Motor wires connected to the socket.

 

 

Track wires from loco and tender connected, and then routed to the 8 pin socket.

 

 

Firebox flicker LED / 1K ohm resistor prepared.

 

 

A 3mm diameter hole was drilled in the back plate.

 

 

LED installed using black tack, with wires Blue (+ve common) and Green (AUX 1) for firebox flicker - coal shovelling.

 

 

Zen 3 wire stay alive installed, and connected to the decoder. Black (GND), White (CTRL) and Blue (+ve).

 

 

 

 

Front loco lamps were installed. 0.4mm diameter holes were drilled for the wires, and routed as shown. Blue wire to a 50K ohm resistor, and then connected to both positives of the LED lamps.

 

 

White (purple in this case), wire for front lamps connected to negative legs of LED lamps.

 

 

The speaker wireswere  connected to brown wires on the decoder, then lots of tidying up. It was difficult to get the loco body back on until the wires were well secured with insulation tape as shown below. The decoder was sited in the roof of the locomotive body, and aligned properly in front of the motor.

The wires were checked on each side in turn to prevent trapping.

 

 

Tested, with lighting and stay alive working fine.

 

 

 

 

The sound from the EM1 is tremendous!

 

HOWEVER: The function of the lamps is not as desired.

I would prefer to have independent control of the front lamps and the tender rear lamp.

 

I am thinking of doing this modification:

a) connecting common blue to the front lamps, and returning to 'connected' yellow and white wires. That should have the front lamps working On / OFF with F0 in both forwards and reverse directions?

b) connecting the blue common to the rear lamp and returning via the purple wire AUX2. Then F20 would control the rear lamp?

 

I expect that I might need to change the F20 function mapping, as currently for the smoke generator?

 

This is a little new to me, so could do with some advice.

 

Edited November 29, 2023 by zr2498
Extra info added

[Hamburger]

HI,

 

b)

if you are ok with keeping F20 (for the rear light) and dropping the smoke generator, you don'have to change the mapping.

You just have to change the output settings for Aux2 from "smoker output" to "lighting output" and this can be done by

CV31 = 16

CV32 = 0
CV283 =  1
CV286 =  20

where CV286 is the brightness (range from 1 to 31).

When changing brightness for this output you always have to program CVs 31/32 in advance as shown above.

 

a)

For the front light you indeed can connect white and yellow, this is authorized by ESU.

This is easier than remapping.

[zr2498]

Having looked at the decoder files with Lokprammer, if I want to Change F20 - AUX 2 (1) from smoke generator to dimmable light with max'm brightness, then this is the change to CVs. Hopefully - I will try after a wiring change (perhaps)?

 

 

 

 

 

 

Edited November 29, 2023 by zr2498
Corrected - Unticked rule 17

[Hamburger]

Correct but you should untick "Rule 17 forward" as this is meant for US Diesel locos. 

CV283=1 in my previous post was meant for light without fade in/out.

[zr2498]

1 minute ago, Hamburger said:

HI,

 

b)

if you are ok with keeping F20 (for the rear light) and dropping the smoke generator, you don'have to change the mapping.

You just have to change the output settings for Aux2 from "smoker output" to "lighting output" and this can be done by

CV31 = 16

CV32 = 0
CV283 =  1
CV286 =  20

where CV286 is the brightness (range from 1 to 31).

When changing brightness for this output you always have to program CVs 31/32 in advance as shown above.

 

a)

For the front light you indeed can connect white and yellow, this is authorized by ESU.

This is easier than remapping.

Thanks @Hamburger You have offered a solution at the same time as me having a look at the files via Lokprogrammer.

I guess CV283 could be 1 or 2 depending on fade in / out.

This seems easier than remapping so I will keep F20.

I very much appreciate your help and feel a little more confident about making the change. Cheers!

[Hamburger]

😄

Didn't know you have a LoPro.

 

[zr2498]

13 hours ago, Hamburger said:

😄

Didn't know you have a LoPro.

 

Learning how to use the LoPro. Much easier than trying to understand the manual.

Changes made this morning, and now working as desired. F0 for front lamps and F20 for rear lamp.

Longest time involved was trying to get the loco body back on again!

[Hamburger]

The learning curve can be steep.

A little trick for the future: it may help if the LoPro shows you all the respective CVs:

 

Go to "Tools -> Program settings -> General settings" and tick the box "Show CV numbers", then close the program and open again.

Now it should show you the respective CV# for each function setting.

 

Nomenclature:

[CVxxx.y] means "only bit y of CVxxx is used for this setting" (mainly on-off-functions)

[CVxxx.y:z] means only bits z to y are used for this setting  (example CV262.4:0 means bits 0 to 4 are used (gives you single-bit-values from 1 to 16, if all bits are on and added this gives you value 31))

[CVxxx.y (CV32=0)] means that CV31 has to be set to 16 and CV32 to 0 before programming the "main" CV. If CV31 needs to have a value other than 16, this will be specified separately).

 

Hard to understand at the beginning and maybe useless for a beginner but after some time you will appreciate this.

Good luck!